Why are there ads?

We would love to provide everyone an ad-free experience, but we do need to generate revenue to cover at least some
of our overhead. We're trying to be as reasonable as possible, and it also allows us to continue to offer you an
option to access KenKen puzzles for free. For those who prefer an Ad-Free playing experience, we have
an option for
just pennies-a-day and it can be canceled anytime. BONUS! KenKen Premium also allows you to Track Your Progress,
Join The Leaderboard, Save Puzzles, and more. Please consider this option for the best experience.

In addition, we continue to offer -- pro bono -- our KenKen Classroom
Program which provides free KenKen puzzles
and lessons to over 1 million students weekly. Revenue we raise from advertisements and subscription sales allow us
to keep the program going, plain and simple. So thank you for supporting these teachers and students by supporting
us. We all appreciate it.

What's KenKen?

So What Is KENKEN, Anyway?

It’s not a crossword. It’s not some extreme version of tic-tac-toe. So what is KENKEN and where did it come from?
Simply put, it’s a grid-based numerical puzzle that uses the basic math operations—addition, subtraction,
multiplication, and division—while also challenging your logic and problem-solving skills. By altering the size of
a KENKEN grid, from 3 x 3 up to 9 x 9, and employing different combinations of the math operations, five different
difficulty levels can be generated, and a seemingly endless number of puzzles. (And many players seem determined
to try them all!) In a way, KENKEN is like a game of pool or even chess: The more you think ahead to your next
move and consider all the possible outcomes, the better you’ll get—and the smarter you’ll become!

KENKEN was developed in 2004 by… no, not two guys named Ken… it was acclaimed Japanese mathematics instructor
Tetsuya Miyamoto. His goal was to improve his students’ math and logic skills. And what better tool than a puzzle?
So he developed one that would be understandable, fun, and challenging for any level of student. Most importantly,
he wanted the puzzle to encourage independent thinking, emphasizing trial and error, concentration, and
perseverance. Mr. Miyamoto’s educational philosophy boils down to “The Art of Teaching Without Teaching.™” His
methods and puzzle were immediately successful.

So KENKEN was born in the classroom. But the puzzle was too addictive to stay in school. It quickly became a
favorite leisure activity for all ages throughout Japan and then for millions of players worldwide. In 2008,
Nextoy LLC brought KENKEN to the United States. Soon, it was the first daily feature since the crossword puzzle to
appear in The New York Times. As its popularity grew, KENKEN appeared in the Los Angeles Times, Chicago Tribune,
The Times of London, Scholastic classroom magazines, and more than 100 other national U.S. publications.
Simultaneously, it is utilized by an ever-growing network of teachers coast-to-coast who praise its academic
value.

Now with enhanced online and mobile versions, KENKEN is expanding its reach even further. Whether in the
classroom, on the beach, waiting for a bus, standing atop a mountain—anywhere you might be—KENKEN is always
stimulating your brain. It’s the puzzle that makes you smarter!

JOIN US

CONTACT US

Welcome to KENKEN!

No matter what you're looking for — learning or fun — KenKen.com has it! Free online puzzles.
Cool math games. Number games. (More addictive than Sudoku or Kakuro? You decide!) Educational games for kids.
Visit our For Teachers section for math teacher resources, our free KenKen Classroom program, and a message
from Tetsuya Miyamoto, the Japanese educator behind KenKen. Miyamoto, chess master David Levy, and the rest of
Team KenKen have crafted these math puzzles into great games for learning and brain training. Need even more
KenKen? Check out our Will Shortz Presents books. Try our mobile app on iPhone and iPad or our Kindle version.
Play on the New York Times puzzle page and NCTM website. Regardless of why, how, or where you play, KenKen are
the math puzzles that make you smarter!